A little more leftover code from the PostGIS Cookbook— a little tool for making pyramids for SFCGAL enabled PostGIS databases. https://github.com/smathermather/postgis-etc/blob/master/3D/pyramidMaker.sql Edit: Actually, I think this would work without SFCGAL, but what would be the point… . Edit 2: Let’s embed some code: Continue reading More cutting room floor stuff… — 3D pyramid maker
ST_3DIntersection performs volumetric intersections for us in PostGIS, if we have SFCGAL enabled for our PostGIS back end. Much like a normal PostGIS intersection, this is the mathematical definition of an interesection, so it returns the volumetric portion of the intersection, plus 3D linestrings and 3D points and other bits and pieces that qualify for the intersection. As a little patch, I wrote a quick … Continue reading More cutting room floor stuff… .
Still working furiously on final edits for the PostGIS Cookbook. My last chapter is the last one that the Packt editors and managers are waiting for, but it will be the best I’ve contributed to the book, so I think it will be worth everyone’s time. The trick with this chapter is that when I first wrote it, it was before the heavy lifting the … Continue reading O man. Epic 3D on its way. I could drone on and on about #postgis
I have been working a bit to get horao working to visualize PostGIS 3D data. In the mean time, I have a little work around for viewing 3D extrudes a 3Dish way (i.e. isometric) The nightly build of QGIS now allows you to visualize polyhedral surfaces, the output type of ST_Extrude. So, I cheated. ST_Extrude takes 4 parameters: an input geometry, and extrusion along the … Continue reading ST_Extrude screen shot: PostGIS with SFCGAL
The guys from Oslandia are really ripping things up in the PostGIS 3D world. (They are nice guys too– Olivier and Hugo had a skeletonization approach punched up and ready to test before I left the Boston Code Sprint this past Spring.) So I missed these two videos in my first few views of the SFCGAL website: ————————————————————————————- Just one question– what is “Horoa plugin … Continue reading PostGIS with SFCGAL — Videos, how did I miss these videos?
So, for those of you who haven’t seen it, SFCGAL, “a C++ wrapper library around CGAL with the aim of supporting ISO 19107:2013 and OGC Simple Features Access 1.2 for 3D operations” is now an optional include in PostGIS (I believe beginning with 2.1, forgive me if I’m wrong). This was a quiet outcome of the Boston Code Sprint, after Paul Ramsey declared exact rational number … Continue reading PostGIS with SFCGAL
In an upcoming recipe (another one for the cutting room floor), we’ll play a bit with realistic biking distances, as compared with a 5-mile buffer (light grey), a 5-mile driving distance (dark grey), and a 5-mile biking-on-roads-with-speed-limits-under-40mph (purplish). This is just a teaser for mapbaker… . Continue reading Realistic biking distances, pgRouting
So, as we’re are in the final edits of the PostGIS Cookbook, there are some recipes that have ended up on the cutting room floor. Several of these will end up on this blog: Amongst those that will end up in the alternate pipeline, and thus ultimately in GitHub, will be a project called pgOrthogonalize, similar to the functionality in Potlatch2 and iD to square … Continue reading PostGIS Cookbook Promises
All goes well, the PostGIS Cookbook will be out in January here’s some of the official info: If you are a web developer or a software architect, … and want to expand the range of techniques you are using with PostGIS, then this book is for you… . An easy-to-use guide, full of hands-on recipes for manipulating spatial data in a PostGIS database. Each topic … Continue reading (a tagged repost) Happy #postgis day, everybody! A big and fun day
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